Electrically operated door lock



Sept. 15, 1964 s. DURAN-r l ELECTRICALLY OPERATED DOOR LOCK Filed Aprill5, 1963- United States Patent O 3,148,525 ELECTRECALLY OPERATED DUURLCK l Sidney I. Durant, 333@ Nestrantl Ave., Brooklyn, NX. Filed Apr.i5, 1963, Ser. No. Nitti@ It? Claims. (Cl. 79-107) This inventionrelates to a door lock in general and more particularly to a door lockwhich is operated electronically.

The conventional door lock is usually aixed to a hinge mounted door. Thelock ordinarily comprises three essential elements: a dead bolt; atongue; and a tumbler mechanism. These elements are mechanically linkedto interact in response to a rotation of the tumbler mechanism cylinder.In the locked state the dead bolt and the tongue are extended to engagean aperture in a so-called striker plate on a stationary member tothereby restrain movement of the door about the hinges.

In the prior art the tongue is usually biased to the extended positionby a spring. When the door is closing a portion of the striker platestrikes an arcuate section ofthe tongue to thereby automatically depressthe tongue. When the door is completely closed the spring again extendsthe tongue to engage the aperture in the striker plate. A rotation ofeither the tumbler cylinder, the inner door knob or, under certaincircumstances, the outer door knob will cause the tongue to be withdrawnfrom engagement with the aperture in the striker plate. The dead bolt,on the other hand, may only be extended or retracted by a rotation ofeither the tumbler cylinder or a. separate knob on the inside of thedoor.

In operation, the tumbler mechanism cylinder is not free to rotate,however, when the correct key is inserted into the tumbler mechanism thetumblers are adjusted, in the well known manner, to allow the cylinderto freely rotate. If the lock is in the locked state, a rotation of thecylinder will cause the dead bolt to be withdrawn from engagement withthe stationary member (i.e., the striker plate). A further rotation ofthe cylinder will disengage the tongue; this operation frees the doorfrom the restraining action of the lock thereby allowing the door to beopened.

There are several disadvantages associated with the above described typeof arrangement. The primary drawback is that further manual operationsare required to operate the dead bolt to securely lock the door afterthe door has been shut. That is, simply closing a door will cause thetongue to engage the striker plate. However, this operation alone isinsufl'cient to securely lock a door because it has been found that thetongue may be forced out of engagement with the striker plate by meansexternal to the lock. In a great many situations a person may not havethe time or the inclination to stop, insert the key in the tumblermechanism, and rotate the cylinder to thereby extend the dead bolt.Similarly, a great majority of people, upon entering through a door,allow the door to close behind them without ever giving a second thoughtto operating the dead bolt portion of the lock. The common fallacy thatthe tongue portion of the lock in itself is adequate to affordsui'licient protection in locking a door has led to many a burglarizedhome or apartment. A second disadvantage to the conventional lock is therequirement of rotating the tumbler mechanism cylinder to eifectretraction of the dead bolt and tongue. This is an extremelyinconvenient operation to perform when a persons hands are otherwiseoccupied as, for example, when one is carrying packages.

Accordingly, it is a general object of the present invention to improvethe operation of door locks. More specie objects of this invention areto minimize or eliminate the above-described difficulties with a lock ofa single straightforward design.

ice

Another object of the present invention is to provide a door lock whichrequires a minimum of manual operations to perform its functions.

Accordingly, a preferred embodiment of the present invention comprises adead bolt and a tongue slidably mounted within a lock body wherein eachis operable between an extended and a retracted position. The :tongue isbiased toward the extended position. A pin on the dead bolt engages thetongue when these elements are in their extended position to insure thatthe tongue will retract in unison with the dead bolt. A magnetic rod isconnected to the dead bolt and two coils concen- .trically surround therod. A source of power is connected to the lock through contacts on thestriker plate.

The opening cycle of the lock is initiated when the correct key isinserted into the tumbler mechanism. This action completes a circuitthereby disabling a latch which prevents movement of the dead bolt andenergizing the first of the two coils. The magnetic field produced bythe coil exerts a force on the rod in a direction which causes the deadbolt, and concomitantly the tongue, to retract thus allowing the door tobe opened. When the tongue and dead bolt reach their retracted positiona device within the lock disables the interconnecting pin and the tongueis again biased toward its extended position.

The closing cycle of the door is initiated when the door is shut. Thus,closing the door causes the tongue to be depressed by the striker platein the conventional manner. The retracted tongue causes a set ofcontacts to close, thereby connecting the source of power to the secondof the two coils. The magnetic field produced by this coil exerts aforce on the rod in a direction which causes the dead bolt to move toits extended position.

Accordingly, a feature of this invention is to provide a door lock whichautomatically dead bolts when the door is closed.

Another feature of the present invention is to provide a door lockwherein the tongue and dead bolt will disengage from the striker platesimply by inserting the key into the tumbler mechanism.

A further feature of the present invention is to provide a door lock inwhich movement of the elements is initiated by electromagnetic devices.

Still another feature of the present invention resides in the use of astop latch to prevent movement of the dead bolt by external means whenit is in the extended position.

Many types of electrically operated locks can only be operated byenergizing the various elements. This type of arrangement can lead todisastrous consequences, i.e., if a tire breaks out and causes a powerfailure before the tenants operate the lock they will not be able toopen the door.

Accordingly, a still further feature of the present invention is toprovide an electrically operated door lock which incorporates amechanical over-ride to manually open the lock in case of power failure.

The above and other objects and features of the present invention willbecome more apparent from a consideration of the following detaileddescription when taken in conjunction with the drawings in which:

FIG. l is a front elevation of the lock of the present invention withthe cover removed and the elements in their extended positions;

FIG. 2 is a sectional view of the lock of the present invention takenalong the lines 2 2 of FIG. l showing a portion of the elements of thelock;

FIG. 3 is a perspective view of a striker plate for the lock shown inFIG. l;

FIG. 4 is an enlarged sectional view of the pawl shown in FIG. l;

FIG. is a sectional view of the tumbler mechanism of the presentinvention with the key inserted;

FIG. 6 is a schematic circuit wiring diagram showing how the electricalelements of FIG. 1 are connected; and

FIG. 7 is a side elevational portion of a door with the externalelements of the lock of the present invention affixed thereto.

It is to be understood that like numbers in the different figuresindicate the same elements.

The preferred embodiment of the present invention is shown in FIG. 1 inthe locked state and comprises a lock 19 having a body portion 12 and aface plate 13. A cover portion 14 (FIG. 2) ts over body 12 and containstwo apertures, 15a and 15b therein. A pair of screws 17a and 17b areadapted to pass through apertures 15a and 15b, respectively and engagethe threaded bores 19a and 19b, respectively, in body 12 therebysecuring the cover to the body. The apertures 21, having countersunkportions 23, are at each end of face plate 13. Screws (not shown) areadapted to pass through these apertures to mount body 12 to a door. Thecountersunk portions 23 receive the heads of the screws so the heads donot project beyond face plate 13.

A dead bolt 16, which has a head portion 13 and a shank portion 20, isslidably mounted within body 12 between the posts 22 and 24. A suitableaperture 43 in face plate 13 allows head portion 1S to extendtherethrough. A stop 25 at the end of shank Ztl engages posts 22 and 24to limit the distance which head 18 extends beyond face plate 13. In theunlocked state stop 25 will abut the rear wall of body 12 to limit thedistance dead bolt 16 will retract within body 12.

A magnetic rod 26 is connected to the rear face of head portion 18 andlies in a plane which is parallel to the axis of travel of dead bolt 16.A bushing 29, which has a bore 31) therein to receive rod 26,concentrically surrounds rod 26 and is mounted on a pedestal 31.Pedestal 31 is rigidly connected to the rear wall of body 12 by thesupports 33 and 34. The two coils 27 and 28, are wound about bushing 29in a manner such that the force one coil will cause to be exerted on rod26 will be opposite to the force the other coil will cause to be exertedon rod 26 when the coils are individually energized.

A relay 54, which is attached to body 12 by a screw (not shown),includes an armature 55 pivotally mounted to body 12 by screw 56. Whenthe dead bolt is extended armature 55 falls below the step 11 in shank20, as shown in FIG. 1, to prevent retraction of head bolt 16. When thewinding of relay 54 is energized, as noted hereinbelow, armature 55moves toward the winding about screw 56 so dead bolt 16 may retractuninhibited.

A tongue 35, having a head portion 44, an enlarged shank portion 37 anda small shank portion 38 is slidably mounted within body 12 between post24 and a post 39. Head 44 comprises, in part, an arcuate portion on therear face thereof. A coiled spring 40, which is affixed to body 12 bypin 41, abuts the rear wall of shank 37 and forces tongue 35 toward theextended position through a suitable aperture 42 in face plate 13. Astop 45 which is affixed to the rear of head 44, abuts the back of faceplate 13 and limits the maximum extension of tongue 35 beyong the faceplate.

An extension d6 is rigidly aixed to shank 20 and contains a bore 47therein. A pin 48, having a beveled washer 69 at one end thereof, iscontained within and free to move in bore 47 and is biased in a downwarddirection by a spring 5t). A detention 51 in enlarged shank 37 receivesthat portion of pin 48 which lies below washer 49. An abutment 52, whichis affixed to body,12, has a beveled face 53 which coacts with washer49, in the manner described hereinbelow, to lift pin 48 out ofengagement with shank 37. Stop 45 serves to limit rearward travel oftongue 35 by abutting extension 46 when dead bolt 16 is in its retractedposition.

A pawl 57, composed of a suitable dielectric material,

is slidably mounted Within a channel 58. A right angled rod 59, which isconnected to shank 38 of tongue 35, is positioned so the end 59a engagesthe front face of pawl 57 and moves the pawl toward a rearward position(to the right in FIG. l) when tongue 35 moves toward the retractedposition. A multiply angled rod 60 is connected to shank 211 of deadbolt 16 and has a hook 61 at the end thereof. The hooked end 61 isoperatively positioned to engage the rear face of pawl 57 and move thepawl toward the foreward position (to the left in FIG. 1) when dead bolt16 moves toward its extended position. A stop 62 on body 12 limits theforeward travel of pawl 57.

FIG. 4 shows an enlarged view of pawl 57. The rear face of the pawl hasan arcuate portion 57a, with notches 57b and 57C at the ends thereof.Operatively positioned to the right of channel 58 (as shown in FIG. l)and in the path of travel of pawl 57, is a set of spring contactscomprising contact 74a (having a raised portion 75 at the end thereof)and contact 7l-b affixed to body 12 by the dielectric block 76. Thus, onthe rearward travel of pawl 57 notch 57e impinges upon 75 therebyforcing contacts 74a and ib together. The pressure of 74a maintains thepawl in place until rod 61 moves the pawl to the right as taken in FIG.1, whereupon contacts 74a and 74b separate.

The tumbler mechanism of the present invention is illustrated in sectionin FIG. 5 and comprises a partially threaded body 63, of a suitabledielectric material, with a keyshaft therein to slidably receive a metalkey 64. An insulated portion 64a on key 64 insulates the handle portionof 6d from the keyed portion. A set of metal tumblers 65a, 65h, 65e and65d are slidably mounted in longitudinal bores in body 63 in theconventional manner. A dielectric plate 66, having a set of contacts67a, 67h, 67e and 67d therein, is axed to the leg 63a of a U shapedmember 68. A pin 79, which engages an aperture in 68, pivotally mountsmember 68 to a post 69 which is affixed to body 63. When the key 64 isinserted in body 63, the top edge of tumblers 65a-65d fall into tbe sameplane. Contacts 67a-67d are forced into engagement with the respectivetumbler when the front end of key 64 abuts the leg 681: of member 68. lfan incorrect key is inserted into body 63 (i.e., a key which is notdesigned to operate the lock) the top edge of the tumblers will not liein the same plane. Thus, contacts 67a-67d will be prevented fromengaging all the respective tumblers since the top edge of the highesttumbler will prevent the lowering of plate 66. Each of the contacts67a-67d is connected to a different prong of a four-prong male socketmounted to the rear of body 63; 67a being shown connected to prong112:1. A pair of springs 71 normally bias plate 66 above the tumblers.

A bore 3 in body 12 (FIG. 1) slidably receives body 63 with projection113 on body 12 engaging a suitable channel therein. A set screw 72,threadably mounted to body 12 through a threaded aperture 73, is turneduntil the rear end thereof abuts body 63 thereby holding the lockmechanism in place. A female socket 114, mounted to body 12, receivesthe prongs of 115 in slidable engagement. The various electricalconnections are omitted in FIG. l for clarity but are shown in detail inFIG. 6.

A pair of wiper contacts 77a and 77b are set in a suitable dielectric 78in the front of face plate 13. Leads 89a and tb respectively connectcontacts 77a and 77b to the electrical elements in body 12, as notedhereinbelow.

The striker plate of the present invention is illustrated in FIG. 3 andcomprises the rectangular body 81 having a laterally extendingprotrusion 82. The striker plate is affixed to a door frame by a pair ofscrews (not shown) passing through the apertures 83. A rectangularaperture S4 slidably receives tongue 35 and dead bolt 16 in theconventional manner to thereby restrain movement of the door. Moreover,protrusion 82 causes tongue 35 to depress in the well known manner, whenthe tongue impinges upon the protrusion as the door is shut. Adielectric block S5 is mounted within body 81 and contains contacts 86aand 86b therein. These contacts are connected to a source of power (notshown in FIG. 3) by the leads 87a and 87h, respectively. Leads 88a and8gb designate a means of providing auxiliary power by connecting, forexample, a battery thereto if the main source of power fails. Theseleads may be connected to the outside of the door frame or any othersuitable place. When the door is shut (i.e., when face plate 13 isopposite body 81) wiper contacts 77a and 77b will respectively engagecontacts 36a and 86b to thereby energize the electrical portions of thelock as described hereinbelow.

A rod 89, having a reduced diameter portion 92 at the end thereof,projects through a suitable aperture in cover 14 and may be supported bya handle 9i), as shown in FIG. 7. (The lock in indicated generally bythe numeral 1t) in FIG. 7.) Handle 90 is affixed to the rear of a door109 by fasteners 91 and slidably supports rod 89, which passes through abore in door 109. A spring 93, compressed between cover 14 and a stop 94on rod 89, forces rod 89 toward the right as taken in FIG. 7. In thenormal position reduced diameter portion 92 rests against contact 95a ofa set of contacts which include contacts 95b and 95C (FIG. l). Thus,when rod 89 is pushed inward toward body 12 the enlarged diameter of rod89 forces contacts 95a and 95h to engage contact 95C. What the pressureis removed, spring 93 forces rod 39 back to its original positionthereby allowing contacts 95a, 95b and 95C to separate.

The electrical elements described above are connected as shown in FIG.6. A source of potential 96 is connected to contacts 86a and S6b byleads 87a and 87b, respectively. (A noted hereinabove, leads 38a and 88hmay be connected to a secondary source of power 97 if primary source 96fails.) If the door is assumed shut wiper contacts 77a and 77b willrespectively engage contacts 86a and 86h thereby connecting source 96across leads Stia and Stlb. Lead 801: is connected to one terminal ofcoil 23; the other terminal of coil 28 is connected to contact 67d onplate 66 by a lead 98. Contact 95a is connected to lead 98 by a lead 4.Lead 80a is connected to contacts 67b and 67e on plate 66 and tocontacts 95e and 74a. One terminal of coil 27 is connected to lead 80bby a lead 99; the other terminal of coil 27 is connected to contact 74hby a lead 100. Coil 54 is connected between lead Sb and contact 951; bythe respective leads 101 and 102. Contact 67a on plate 66 is likewiseconnected to lead 102.

In operation, assume that a door utilizing the device of the presentinvention is shut with dead bolt 16 and tongue 35 extended to engageaperture S4 and contacts 86a and @6b respectively connected to wipercontacts 77a and 77b. When key 64 is inserted in the keyshaft in tumblermechanism body 63, tumblers 65a through 65d will respectively engagecontacts 67a through 67d, in the manner noted above. Thus, as can beseen from FIG. 6, the winding of relay 54 will be energized through thecircuit comprising source 96, lead 87h, contacts S611 and 77b, leads band 101, the winding of relay 54, lead 102, Contact 67a, tumbler 65a,key 64, tumbler 65h, contact 67b, lead 86a, contacts '77a and 86a andlead 87a. The energizing of relay 54 will cause armature 55 to risethereby allowing dead bolt 16 to retract unimpeded, as noted above. Coil28 will be energized through the circuit comprising source 96, lead 87a,contacts 86a, and 77a, lead 80a, contact 67C, tumbler 65e, key 64,tumbler 65d, contact 67d, lead 98, coil 28, lead Sb, contacts 77b and86h and lead S'b. Coil 28 is wound in such a direction as to attractmagnetic rod 26, according to the Well known principles ofelectromagnetic theory. Thus, dead bolt 16 (the head 1S of which isrigidly connected to rod 26) will be drawn back towards its retractedposition thereby causing tongue 35 to move towards its retractedposition by virtue of the interconnecting pin 43 engaged in detention51. Pressure applied to the door wiil cause the door .to open oncetongue 35 and dead bolt 16 have retracted a distance suiiicient to causethem to be disengaged from aperture 84. Once the door has begun to opencontacts 77a and 77b will become disengaged from contacts 86a and S6bthereby de-energizing coil 2S. However, the momentum of dead bolt 16will carry it to its fully retracted position causing beveled washer t9to engage face 53 of abutment S2 thereby raising pin i8 and freeingtongue 3S as explained hereinabove. Spring 4@ forces tongue 35 Ito itsextended position. Key 6d may then be removed from body 63.

The closing cycle is initiated when the door is shut. The arcuateportion of tongue 35 will impinge upon extension 82 forcing the tonguetoward its retracted position. Right angle rod 59 will engage the frontface of pawl S7 and move pawl 57 to impinge upon extension 75 therebyforcing contacts 74a and 74h into engagement, as described above.Although tongue 35 is again extended, by spring 4t), through aperture84, the contacts 74a and 74h will remain in engagement since their forceon pawl 57 will keep the pawl in place. Since the door is closed leadsStia and Slb will be energized because contacts 77a and 77b willrespectively engage contacts 86a and 86h (which are connected to source96 by leads 87a and 37b, respectively). Thus, coil 27 will be energizedthrough the circuit comprising lead Stia, contacts 74a and 7411, lead16), coil 27, lead 99 and lead 80h. Coil 27 is wound in such a directionas to cause magnetic rod 26 to move to the left as taken in FIG. l. Thisaction will torce dead bolt 16 to its extended position thereby causinghead 18 to be engaged in aperture 84. As dead bolt 16 moves to itsextended position the hooked end 61 of rod 66B will engage the rear faceof pawl 57 and move .the pawl Ito the left as taken in FlG. 1. As pawl57 moves toward the left it releases the force exerted on contacts 74aand 74h and these contacts separate thereby cie-energizing coil 27.Armature 55, which lies on surface 11 of shank 2,@ while dead bolt 16 isin its retracted position, will fall into position when the dead bolt isextended to prevent movement of the bolt as explained above. Hence, itis to be noted, in accordance with the present invention, that the lockautomatically dead bolts upon closure of the door.

lt is to be noted that although rod 59 on tongue 35 engages pawl 57 andmoves the pawl to the right as taken in FIG. 1 when the tongue Iretractson the opening cycle, the forces involved may not be suflicient to forcethe pawl to maintain contact with raised portion 75 on contact 74a.However, even if contacts 74a and 74b are forced together, coil 27 willnot be energized since no source of power will be connected to wipercontacts 77a and 77b when the door is open.

lf it is desired to unlock the door from the inside, rod S9 is pushedtoward the left as taken in FIG. 7. The enlarged diameter of rod 89forces contacts 95a and 95h into engagement with contact e (FIG. 6).Thus, relay 5d will be energized through the circuit comprising source96, lead 87a, contacts 86a and 77a, lead 80a, contacts 95C and 95h, lead162, the winding of relay 54, lead 101, lead 56h, contacts 77b and Sband lead 87b. Coil 2? will be energized through the circuit comprisingsource 96, lead 87h, contacts @6b and 77b, lead 81911, coil 28, lead 98,contacts 95a and 95C, lead Stia, contacts 77a and 86a and lead 87a. Withrelay 54 and coil 26 energized, dead bolt 16 and tongue 35 will retractin the manner noted hereinabove. Thus, the door may be opened by pullingon handle 9).

On many occasions it may be desirable to operate the lock of the presentinvention by mechanical means such as when the primary source of powerfails and an emergency does not leave time to connect a secondary sourceor power' to the lock. This mechanical over-ride may comprise a lever193 pivotally mounted to shank 20 of dead bolt 16 by means of pin 1M,which is afxed to shank 29, passing through an aperture in 103. The

top edge of level 193 is biased to the right, as taken in FIG. l, by aspring 368 which is connected between the top portion of lever 193 andshank 2d. The lower portion of lever 93 contains an aperture 16S whichreceives a lead i therein. Lead H26 is wound about a pulley 107 andpasses through an aperture in cover plate 1d and through a bore in door109 to terminate in a pull ring il() (FIG. 7).

It the lock is in its locked state and the source of power fails, ringil() is pulled thereby tensing lead ldd. Lead 1636 will exert a force onlever 163 in a direction which will force the top edge of lever 103 tothe left as taken in FG. l, against the action of spring 10S. The topedge of lever 103 will impinge upon armature 55 thereby forcing thearmature up and out of the path of travel of dead bolt 16. Continuedforce on lead M26 will be transmitted to shank by virtue of pin 104connecting the lever E03 and dead bolt 16 thereby forcing the dead bolttoward its retracted position. The dead bolt 16 will cause tongue 35 toretract, in the manner noted hereinabove, to thereby unlock the door. Apull on handle 96 will cause the door to open.

What is claimed is:

1. A door lock comprising, in combination, a lock body, a dead boltmoveable in said lock body between an extended and a retracted position,a tongue moveable in said lock body between a retracted and an extendedposition, means for biasing said tongue toward its extended position,first means responsive to an electric current for moving said dead boltfrom the extended to the retracted position, second means responsive toan electric current for moving said dead bolt from the retracted to theextended position, energizing means for providing a source of current,means responsive to the insertion of a key for connecting saidenergizing means to said first means, means actuated by said tongue forconnecting said energizing means to said second means, latching meansfor connecting the tongue and dead bolt together when said tongue anddead bolt are in the extended position, and means for disabling saidlatching means when said dead bolt reaches a predetermined position inits travel from the extended to the retracted position.

2. A door lock comprising, in combination, a lock body, a dead boltmoveable in said lock body between an extended and a retracted position,stop means for preventing movement of said bead bolt when it is in theextended position, a tongue moveable in said lock body between anextended and a retracted position, means for biasing said tongue towardits extended position, latching means for connecting said tongue anddead belt together when they are in the extended position, first meansresponsive to an electric current for removing said stop means, secondmeans responsive to an electric current for moving said dead bolt fromthe extended to the retracted position, third means responsive to anelectric current for moving said dead bolt from the retracted to theextended position, energizing means for providing a source of electriccurrent, means responsive to the insertion of a key for connecting saidenergizing means to said rst and second means, means actuated by saidtongue for connecting said energizing means to said third means, andmeans for disabling said latching means when said dead bolt reaches apredetermined position in its travel from the extended to the retractedposition.

3. A door lock as defined in claim 2 including, a rod protruding fromsaid lock body and moveable therein, biasing means for biasing said rodaway from said lock body, and means actuated by said rod when said rodis moved in toward said lock body for connecting said energizing meansto the first and second means.

4. A door lock as defined in claim 2 and means responsive to the pullingof a lead for removing said stop means and for moving said dead boltfrom the extended to the retracted position.

5. In `a locking mechanism for a door, the combination comprising, acasing structure, a dead bolt having a head and a shank portion andmoveable in said casing structure between an extended and a retractedposition, a magnetic rod projecting from the rear of said head with themajor axis of said rod lying in a plane parallel to the plane of travelof said dead bolt, a first coil wound in one direction and a second coilwound in the opposite direction, means for mounting said coils toconcentrically surround a portion of said rod, a tongue moveable in saidcasing structure between an extended and a retracted position, means forbiasing said tongue toward the extended position, energizing means forproviding a source of electric current, means responsive to theinsertion of a key for connecting said energizing means to said firstcoil whereby the magnetic field produced by said first coil attractssaid magnetic rod to move said dead bolt from the extended to theretracted position, means actuated by said tongue when said tongue movestoward the retracted position for connecting said energizing means tothe second coil whereby the magnetic field produced by the second coilrepels said magnetic rod to move said dead bolt from the retracted tothe extended position, latching means for connecting said dead bolt andtongue together when said tongue and dead bolt are in the extendedposition, and means for disabling said latching means when said deadbolt reaches a predetermined position in its travel from the extendedposition to the retracted position.

6. In a locking mechanism for a door, the combination comprising, acasing structure adapted to be aflixed to a door, a dead bolt having ahead and a shank portion and moveable in said casing structure betweenan extended and a retracted position, a tongue moveable in said casingstructure between an extended and a retracted position, biasing meansfor biasing said tongue toward the extended position, a striker plateadapted to be affixed to a stationary member and having a aperturetherein for slidably receiving said dead bolt and said tongue, amagnetic rod projecting from the rear face of said head with the majoraxis of the rod parallel to the plane of travel of said dead bolt, afirst coil means concentrically surrounding at least a portion of saidrod for producing a magnetic field which attracts said rod to move thedead bolt to the retracted position, a second coil means concentricallysurrounding at least a portion of said rod for producing a magneticfield which repels said magnetic rod to move said dead bolt to theextended position, a first set of contacts afiixed to said strikerplate, a source of power connected across said first set of contacts,contact means afiixed to said casing structure for engaging said firstset of contacts when the casing structure is in a predetermined positionrelative to said striker plate, means responsive to the insertion of akey for connecting said contact means to said rst coil means to therebyenergize said first coil means when said casing structure is in saidpredetermined position, first means actuated by said tongue when saidtongue moves toward the retracted position for connecting said contactmeans to said second coil means to thereby energize said second coilmeans when said casing structure is in said predetermined position,latching means for connecting said tongue and dead bolt together whensaid tongue and dead bolt are in the extended position, and means fordisabling said latching means when said dead bolt reaches apredetermined position in its travel from the extended position to theretracted position.

7. An arrangement as defined in claim 6 wherein said first meansincludes a pawl having a notched face and moveable by said tongue from afirst to a second position, said first means further including a secondset of contacts connected in series with said second coil means and saidcontact means and operatively positioned in the path of travel of saidpawl whereby the notched face of said pawl impinges upon at least one ofsaid second set of contacts to force said second set of contacts intoengagement when said tongue moves said pawl to the secondposition,

and means connected to said dead bolt for moving said pawl to the iii-stposition when said dead bolt moves toward the extended position.

8. An arrangement as defined in claim 7 and a rod llaving a large and asmall diameter projecting from said casing structure and slidabletherein, second means for connecting said contact means to said rst coilmeans when the large diameter of said rod abuts said second means, andmeans for biasing said rod so the small diameter abuts said secondmeans.

9. An arrangement as defined in claim 7 and a relay means operablebetween a rst and a second position for preventing movement of said deadbolt when said dead bolt is in the extended position and said relaymeans is in the first position and for allowing movement of said deadbolt when said relay means is in the second position, said meansresponsive to the insertion of a key further connecting said contactmeans to said relay means whereby said relay means moves to said secondposition when said casing structure is in said predetermined position.

10. An arrangement as dened in claim 9 and a lever pivotally mounted tosaid dead bolt and operable between a lrst and a second position to movesaid relay means to the second position when said lever is moved to saidsecond position, means for biasing said lever to the iirst position, alead connected to said lever whereby tension on said lead moves saidlever to the second position and moves said dead bolt to the retractedposition.

No references cited.

1. A DOOR LOCK COMPRISING, IN COMBINATION, A LOCK BODY, A DEAD BOLTMOVEABLE IN SAID LOCK BODY BETWEEN AN EXTENDED AND A RETRACTED POSITION,A TONGUE MOVEABLE POSITION, MEANS FOR BIASING SAID TONGUE TOWARD ITSEXTENDED POSITION, FIRST MEANS RESPONSIVE TO AN ELECTRIC CURRENT FORMOVING SAID DEAD BOLT FROM THE EXTENDED TO THE RETRACTED POSITION,SECOND MEANS RESPONSIVE TO AN ELECTRIC CURRENT FOR MOVING SAID DEAD BOLTFROM THE RETRACTED TO THE EXTENDED POSITION, ENERGIZING MEANS FORPROVIDING A SOURCE OF CURRENT, MEANS RESPONSIVE TO THE INSERTION OF AKEY FOR CONNECTING SAID ENERGIZING MEANS TO SAID FIRST